When no kscreen config is available a new one is generated which contains the same ID for the first and second monitor. Starting KDE with this configuration causes a startup failure. 
If i change the ID of the secondary monitor KDE starts normally.

Reproducible: Always

Steps to Reproduce:
1. Remove any kscreen config file from ~/.local/share/kscreen
2. restart KDE
3. KDE fails to start and returns to SDDM
4. Edit the newly generated config file in ~/.local/share/kscreen and change the ID of the secondary monitor (changing one digit is enough)
5. Restart KDE
6. KDE starts without any trouble

Actual Results:  
First and secondary monitor have the same ID in the config

Expected Results:  
Different IDs for first and secondary monitor

GPU "ZOTAC GeForce GT 630 Synergy Edition":
http://www.zotac.com/products/graphics-cards/geforce-600-series/gt-630/product/gt-630/detail/geforce-gt-630-synergy-edition.html

Output of "kscreen-console outputs":
START: Requesting Config
kf5.kiconthemes: "Theme tree: (Breeze)"
kscreen: launcherDataAvailable: "org.kde.KScreen.Backend.XRandR"
kscreen: Primary output changed from KScreen::Output(Id: 638 , Name: "DVI-I-2" ) ( "DVI-I-2" ) to KScreen::Output(Id: 638 , Name: "DVI-I-2" ) ( "DVI-I-2" )
kscreen: Launcher finished with exit code 1 , status 0
kscreen: Service for requested backend already running
kscreen: Primary output changed from KScreen::Output(Id: 638 , Name: "DVI-I-2" ) ( "DVI-I-2" ) to KScreen::Output(Id: 638 , Name: "DVI-I-2" ) ( "DVI-I-2" )
Received config. Took 271 milliseconds
Screen:
	maxSize: QSize(16384, 16384)
	minSize: QSize(8, 8)
	currentSize: QSize(3360, 1050)

-----------------------------------------------------

Id:  636
Name:  "DVI-I-0"
Type:  "Unknown"
Connected:  false

-----------------------------------------------------

Id:  637
Name:  "DVI-I-1"
Type:  "Unknown"
Connected:  false

-----------------------------------------------------

Id:  638
Name:  "DVI-I-2"
Type:  "Unknown"
Connected:  true
Enabled:  true
Primary:  true
Rotation:  1
Pos:  QPoint(0,0)
MMSize:  QSize(474, 296)
Size:  QSize(1680, 1050)
Clones:  None
Mode:  "639"
Preferred Mode:  "639"
Preferred modes:  ("639")
Modes: 
	 "639"    ""   QSize(1680, 1050)   59.8833
	 "640"    ""   QSize(1680, 1050)   59.9543
	 "641"    ""   QSize(1280, 1024)   75.0247
	 "642"    ""   QSize(1280, 1024)   60.0197
	 "643"    ""   QSize(1280, 960)   60
	 "644"    ""   QSize(1152, 864)   75
	 "645"    ""   QSize(1024, 768)   75.0286
	 "646"    ""   QSize(1024, 768)   70.0694
	 "647"    ""   QSize(1024, 768)   60.0038
	 "648"    ""   QSize(800, 600)   75
	 "649"    ""   QSize(800, 600)   72.1876
	 "650"    ""   QSize(800, 600)   60.3165
	 "651"    ""   QSize(800, 600)   56.25
	 "652"    ""   QSize(640, 480)   75
	 "653"    ""   QSize(640, 480)   72.8088
	 "654"    ""   QSize(640, 480)   59.9405
EDID Info: 
	Device ID:  "xrandr-SyncMaster-H1AK500000"
	Name:  "SyncMaster"
	Vendor:  ""
	Serial:  "H1AK500000"
	EISA ID:  ""
	Hash:  "7c58f528b24dbb4a3f62aa7c73a9070e"
	Width:  47
	Height:  30
	Gamma:  2
	Red:  QQuaternion(scalar:1, vector:(0.639648, 0.328125, 0))
	Green:  QQuaternion(scalar:1, vector:(0.299805, 0.599609, 0))
	Blue:  QQuaternion(scalar:1, vector:(0.150391, 0.0595703, 0))
	White:  QQuaternion(scalar:1, vector:(0.3125, 0.329102, 0))

-----------------------------------------------------

Id:  655
Name:  "DVI-I-3"
Type:  "Unknown"
Connected:  true
Enabled:  true
Primary:  false
Rotation:  1
Pos:  QPoint(1680,0)
MMSize:  QSize(474, 296)
Size:  QSize(1680, 1050)
Clones:  None
Mode:  "639"
Preferred Mode:  "639"
Preferred modes:  ("639")
Modes: 
	 "639"    ""   QSize(1680, 1050)   59.8833
	 "640"    ""   QSize(1680, 1050)   59.9543
	 "641"    ""   QSize(1280, 1024)   75.0247
	 "642"    ""   QSize(1280, 1024)   60.0197
	 "643"    ""   QSize(1280, 960)   60
	 "644"    ""   QSize(1152, 864)   75
	 "645"    ""   QSize(1024, 768)   75.0286
	 "646"    ""   QSize(1024, 768)   70.0694
	 "647"    ""   QSize(1024, 768)   60.0038
	 "648"    ""   QSize(800, 600)   75
	 "649"    ""   QSize(800, 600)   72.1876
	 "650"    ""   QSize(800, 600)   60.3165
	 "651"    ""   QSize(800, 600)   56.25
	 "652"    ""   QSize(640, 480)   75
	 "653"    ""   QSize(640, 480)   72.8088
	 "654"    ""   QSize(640, 480)   59.9405
EDID Info: 
	Device ID:  "xrandr-SyncMaster-H1AK500000"
	Name:  "SyncMaster"
	Vendor:  ""
	Serial:  "H1AK500000"
	EISA ID:  ""
	Hash:  "7c58f528b24dbb4a3f62aa7c73a9070e"
	Width:  47
	Height:  30
	Gamma:  2
	Red:  QQuaternion(scalar:1, vector:(0.639648, 0.328125, 0))
	Green:  QQuaternion(scalar:1, vector:(0.299805, 0.599609, 0))
	Blue:  QQuaternion(scalar:1, vector:(0.150391, 0.0595703, 0))
	White:  QQuaternion(scalar:1, vector:(0.3125, 0.329102, 0))

-----------------------------------------------------

Id:  656
Name:  "HDMI-0"
Type:  "Unknown"
Connected:  false